#slider {
    width: 400px;
    height: 400px;
    /* 超出宽度的内容处理方式, hidden: 裁剪 */
    overflow: hidden;
}
#slider .slides {
    display: block;
    width: 6000px;
    height: 400px;
    margin: 0;
    padding: 0;
}
#slider .slide{
    float: left;
    list-style-type: none;
    width: 400px;
    height: 400px;
}